1. Field of the Invention
The present invention relates to a single stage forward-flyback converter and a power supply apparatus for a light emitting diode.
2. Description of the Related Art
In general, in order to drive an electronic device in a domestic, commercial or industrial setting, a power supply apparatus converting commercial power into driving power appropriate for the electronic device and supplying the converted driving power has been adopted in the interior or on an outer portion of the electronic device.
The power supply apparatus may also be adopted in order to drive a light emitting diode.
Recently, interest in and demand for light emitting diodes (LEDs) has increased.
A device using the light emitting diode may be manufactured to be compact to thereby be used in a location in which it is difficult to install an existing electronic product. Further, in the case in which the light emitting diode is used as an illumination apparatus, it is easy to implement various colors of light and control illuminance, such that the light emitting diode may be used as a system illumination apparatus suitable in circumstances including watching a movie, reading books, and having a meeting.
In addition, the light emitting diode consumes an amount of power equal to about of the power consumed by an incandescent lamp, has a lifespan of fifty thousand to a hundred thousand hours, 5 to 10 times longer than that of an incandescent lamp, and is environmentally-friendly as a mercury free light source and may be variously designed.
Due to these characteristics, light emitting diode illumination projects have been promoted as government-backed national projects in a range of nations including America, Japan and Australia, as well as Korea.
As described above, the light emitting diode, the use of which has increased, requires a driving apparatus for the driving thereof. However, as described in the following Related Art Document, in the case of a two-stage configuration including a power factor correction circuit stage performing power factor correction, and a direct current (DC) to DC converter circuit stage for a constant current control of an output load, power conversion efficiency is deteriorated, and in the case of driving an array including a plurality of light emitting diodes, when a required light emitting diode driving voltage rises, manufacturing costs may be increased due to the use of a high voltage element.